function main() {



    var canvas = document.getElementById('android3D');


    var gl = WebGLUtils.setupWebGL(canvas);
    if (!gl) {
        console.log('Failed to get the rendering context for WebGL');
        return;
    }

    canvas.width = window.innerWidth - 30;
    canvas.height = window.innerHeight - 30;
    // android3D1.X_SCALE = canvas.height / canvas.width;
    // android3D2.X_SCALE = canvas.height / canvas.width;
    var android3D1 = new android3D(canvas.height / canvas.width, [0, 0, 0, 1], [0, 1, 0], [0, 0, 1]);

    gl.viewport(0, 0, canvas.width, canvas.height);


    setEye(0, 2, 20);
    gl.clearColor(0.0, 0.0, 0.0, 1.0);
    gl.enable(gl.DEPTH_TEST);

    // rotateMe(gl);
    // rotateEye(gl);
    gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
    android3D1.drawAndroid3D(gl);
    /**
     * 可用方向键控制，左右方向，上下前后移动
     */
    document.onkeydown = function (ev) {
        android3D1.keydown(ev, gl);
    };
}